Intra-sellar aneurysms are a rare, but important consideration when evaluating pituitary masses. Identification of aneurysms is critical to appropriate treatment and avoiding perilous consequences. These vascular aneurysms can result in severe endocrine dysfunction due to mass effect, stripping of the vascular supply to the pituitary, or hemorrhage. Here we describe a novel case of spontaneous myxedema coma and pituitary apoplexy secondary to a large internal carotid artery aneurysm.